The invention relates to a cord equalizer for the lift cords of window shades of the type that are operated by simultaneous equal movement of two or more lift cords. The term window shade is used herein in its broad sense to include window coverings formed of fabric and pleated webs of material as well as slatted blinds and venetian blinds and which are operated by a plurality of lift cords.
Various cord equalizers have heretofore been made for equalizing movement of a plurality of lift cords in window shades and the like. The assignee of the present invention has heretofore made a lift cord equalizer having two body members hingedly connected along one edge by a thin flexible hinge portion, with ribs on the interfaces of the body members arranged to interleave and draw the lift cords into a sinus configuration, when the body members are closed and locked in position. U.S. Pat. No. 4,635,698 discloses a cord equalizer formed of two body members with a barb on one member arranged to press the cords into a sharp edged opening on a second body member, for the purpose of locking the lift cords to the cord equalizer. U.S. Pat. Nos. 2,220,203 and 4,967,824 illustrate clamp devices having slidably interconnected members for gripping cords and cables with a wedge type action.